<!DOCTYPE HTML>
<html>
	<head>
		<meta charset="utf-8" />
		<style>
			#yuan{
				width:96px;
				height:48px;
				border-top:2px solid red;
				border-right:2px solid red;
				border-bottom:50px solid red;
				border-left:2px solid red;
				border-radius:100px;/*备注：圆角的半径大于等于矩形半径，默认都是圆形的  本例中使用50px和100px效果相同*/
			}
		</style>
	</head>
	<body>
		<div id="yuan">
		</div>
	</body>
</html>